I encountered quite a few problems using the SIAM layout. 1. It didn't show theorem numbers in Lyx, just a #. 2. Converting an AMS article to a SIAM article did not work. 3. It didn't output LaTeX correctly http://www.mail-archive.com/[EMAIL PROTECTED]/msg59971.html
Based on the AMS layout files, I hacked together SIAM layout files which work for me. This is my first time ever making layout files, so I may have done it wrong. Anyway, I posted the layout files at: http://cds.gmu.edu/~acorriga/lyx/siamltex.tar.gz<http://cds.gmu.edu/%7Eacorriga/lyx/siamltex.tar.gz>in case that they might be of use to others. Andrew Corrigan